She said: “We have had the Iraqi Kurds who carry knives and the Poles and the Lithuanians.

Anybody in the community, as we know in relation to London, will carry a knife. We have done a lot to tell them not to, and we have seen it go down.” Shadow Home Secretary David Davis said: “Under Labour fatal stabbings are up by almost a third and the Government’s lax approach means people carry knives in the street with impunity.

“We need more effective action to tackle knife possession – regardless of who has them. This means taking a zero-tolerance approach – including action to confiscate such weapons and punish those carrying them.

Only this will send a clear message that we are serious about tackling a problem, which one senior judge has labelled an epidemic.”

Mrs Spence appeared before the Commons Home Affairs Select Committee and also highlighted problems related to violent debt recovery among Eastern European arrivals. She described the trend of growing labour and sexual exploitation, mainly within former Communist communities whose nations have joined the EU since 2004, as “very worrying”.

The impact on resources in her force had been “immense” and the position just six or nine months ago is different to now. And she warned some are arriving to work in the black economy and therefore not showing up in official figures.

Mrs Spence repeated concerns that dealing with foreigners takes two to three times longer because of translation issues or checking the history of people.

Local Government Association chairman Sir Simon Milton said: “Nationally there has been no crime wave but there are instances where there have been spikes in certain types of criminal activity.”

He said parts of the country that were facing “sudden very significant increases” and found it difficult to manage.

Local councils have already attacked the Government’s counting methods following the inflows from the expansion of the EU into Eastern Europe in 2004 – the A8 countries – and last year – the A2 nations of Bulgaria and Romania.

A Home Office spokeswoman said: “The vast majority of foreign nationals entering or living in the UK play by our rules. However, we will not accommodate those that abuse our hospitality by becoming involved in crime.

“The UK Border Agency has a national network of crime partnerships with the police so that we stand shoulder to shoulder with police forces and systematically target foreign law breakers for expulsion.”

EU citizens have freedom of movement within member states but can be deported and barred for 10 years. A leaked report in April warned that EU migration had brought a “huge surge in the exploitation of migrants and organised crime”.